The present invention relates to a remote control signal reception device, and more particularly, relates to a remote control signal reception device in which the infrared ray signal from one remote controller can optically be received by any one of a plurality of signal optical reception parts to avoid the impossibility of the remote control due to noise.
In the case of a projection type display device (projector), there are many cases where it is provided in the state the main body part performing projection is hung down from the ceiling of a building such as a hall or it is used in the state of standing at a given height. In the case where the main body is provided at a certain height or it is hung down from the ceiling, the operator (user) performs the operation and control of the apparatus while seeing the picture projected on the screen. Therefore, in many cases, the direction of the view of the operator and the mounting place of the main body part optically receiving the remote control signal do not agree with each other. As means for solving such a problem, there is a method in which a plurality of signal optical reception parts are provided in different optically receiving directions. This configuration will be described below.
FIG. 1 shows a conventional remote control signal reception device.
The remote control signal reception device 1 optically receives a remote control signal by using an infrared ray from a remote controller 2, and decodes this, and according to that result of decoding, it controls a projection type display device 3. The remote control signal reception device 1 comprises a plurality of remote control optical reception parts 4a, 4b, 4c, 4d that are reception parts having means for receiving a remote control signal by using infrared light and performing photoelectric conversion, an OR circuit 5 connected to these remote control optical reception parts 4a to 4d, a decoder 6 connected to this OR circuit 5, a CPU part 7 (Central Processor Unit) for controlling the projection type display device 3 according to the result of decoding of this decoder 6. The remote control optical reception parts 4a to 4d are arranged so that the remote control signal from the remote controller 2 can be optically received from many directions such as the hack and forth direction, right and left direction, or vertical direction, and they have converting means for performing the photoelectric conversion of the received optical signal and amplifying means for amplifying the electric signal subjected to the photoelectric conversion. From the remote controller 2, the optical signal made by subjecting the electric signal corresponding to the operating contents to the photoelectric conversion and to the optical modulation is transmitted.
In FIG. 1, when the optical signal is transmitted from the remote controller 2, that remote control signal is optically received by one or a plurality of the remote control optical reception parts 4a to 4d. The output signals of the remote control optical parts 4a to 4d are subjected to the OR logic by the OR circuit 5, and inputted into the decoder 6. The decoder 6 decodes the remote control signal and outputs the result thereof to the CPU part 7. The CPU part 7 controls the projection type display device 3 according to the result of decoding. Since the output signals from the remote control optical reception parts 4a to 4d can be composed by the OR circuit 5, one decoder 6 is sufficient.
However, according to the conventional remote control signal reception device, there has been such a problem where in the case where the noise is inputted from one (or a plurality) of remote control optical reception parts 4a to 4d, even when a normal remote control signal is optically received from another remote control optical reception part, the remote control signal is interfered by the noise, and a normal remote control signal cannot be taken out of the signal composed by the OR circuit 5.
In the case where the optical reception part of the remote control signal reception device is provided at the ceiling, when the mounting place is a public facility, a lot of illuminating apparatus are attached to the ceiling. In the case where it is inevitable to arrange the optical emitting part and the optical reception part of this illuminating apparatus facing to each other, and in the situation where they are adjacent to each other, the light of the illuminating apparatus is optically inputted into the optical reception part at a high level. Since the wavelength of this light is wide, it is sensed by the optical reception part and becomes a noise. Furthermore, in the case of an illuminating apparatus whose operating principle is the discharge phenomenon like the fluorescent tube 8, an electromagnetic wave is generated, and it gives effect on the electronic circuit of the optical reception part. Therefore, in the case where the remote control optical reception part is provided near the fluorescent tube 8, the light or electromagnetic wave from the fluorescent tube 8 is received as a noise by the remote control optical reception part (here, the remote control optical reception part 4b) near the fluorescent tube 8. At this moment, if the remote control signal of the remote controller 2 is received by the remote control optical reception part 4c, the remote control signal by the remote control optical reception part 4c and the noise signal by the remote control optical reception part 4b are composed in the OR circuit 5. As a result of this, when the noise signal is large, the remote control signal is affected, and it becomes difficult to decode the remote control signal.
Accordingly, it is an object of the present invention to provide a remote control signal reception device in which it is possible to take out a remote control signal without receiving any effect of the noise even when the reception part receiving the effect of the external noise is provided near the noise source.
In order to attain the above-described object, according to the present invention, there is provided a remote control signal reception device that receives a remote control signal transmitted from a remote controller by one of a plurality of reception parts and controls an apparatus such as a projection type display device on the basis of the result obtained by decoding this received remote control signal, comprising a plurality of decoders connected to one corresponding reception part of said plurality of reception parts and creating a decode signal by decoding the above-described remote control signal and creating an effective signal showing the effectiveness of the above-described remote control signal on the basis of the identification information included in the above-described remote control signal, and a decider selection part for outputting the above-described decode signal on the basis of the input of the above-described effective signal when the above-described decode signal is inputted.
According to this configuration, the remote control signal and noise components are received in a plurality of reception parts. In a decoder connected to each reception part, the identification information in the received remote control signal is extracted, and when this identification information corresponds to the remote control apparatus, an effective signal showing the effectiveness of the received remote control signal is outputted. Based on this effective signal, the decoder selection part adopts only the decode signal of the decoder outputting the effective signal, As a result of this, even when the noise components are inputted into one of a plurality of reception parts, the original operation can be performed if at least one normal remote control signal is received. Accordingly, it becomes possible to surely control a remote control apparatus from a remote place.